Platform: RK3288
OS: Android 6.0
Kernel: 3.10.92
Kernel driver for lp5523
- National Semiconductor LP5523 led driver chip
- Datasheet: http://www.national.com/pf/LP/LP5523.html
Authors: Mathias Nyman, Yuri Zaporozhets, Samu Onkalo
Contact: Samu Onkalo (samu.p.onkalo-at-nokia.com)
Description
LP5523 can drive up to 9 channels. Leds can be controlled directly via
the led class control interface.
The name of each channel is configurable in the platform data - name and label.
There are three options to make the channel name.
LP5523可以驱动最大到9通道。Leds可以直接通过Linux的led class接口来控制。
每个通道的名字可以通过platform data中的name和label来定义，有三种方法可以定义名字。
a) Define the ‘name’ in the platform data
To make specific channel name, then use ‘name’ platform data.
/sys/class/leds/R1 (name: ‘R1’)
/sys/class/leds/B1 (name: ‘B1’)
a) 在platform data中定义"name"
会看到如下形式名字：
/sys/class/leds/R1 (name: 'R1')
/sys/class/leds/B1 (name: 'B1')
b) Use the ‘label’ with no ‘name’ field
For one device name with channel number, then use ‘label’.
/sys/class/leds/RGB:channelN (label: ‘RGB’, N: 0 ~ 8)
b) 在没有"name"域的情况下使用"label"
对于一个device下面有多个channel的情况下，会看到如下形式：
/sys/class/leds/RGB:channelN (label: 'RGB', N: 0 ~ 8)
c) Default
If both fields are NULL, ‘lp5523’ is used by default.
/sys/class/leds/lp5523:channelN (N: 0 ~ 8)
c) 默认上面两种都没有定义的情况时，默认就使用名字"lp5523"
LP5523 has the internal program memory for running various LED patterns.
For the details, please refer to ‘firmware’ section in leds-lp55xx.txt
LP5523内部有一块memory可以用来运行不同的LED pattern。
详细内容可以参考leds-lp55xx.txt的"firmware"章节。
Selftest uses always the current from the platform data.
platform data中的电流值用于做自检测试。
Each channel contains led current settings.
/sys/class/leds/lp5523:channel2/led_current - RW
/sys/class/leds/lp5523:channel2/max_current - RO
Format: 10x mA i.e 10 means 1.0 mA
每个channel包含各自的电流设置，当前电流可读写，最大电流只读，操作路径如下。
/sys/class/leds/lp5523:channel2/led_current - RW
/sys/class/leds/lp5523:channel2/max_current - RO
文件的格式是以10倍于电流数为单位的，比如设置为10，那么实际值是1mA.
如下是对lp5523的配置格式，如果是dts形式，则不适合。
注意： 函数结构填充要加返回值，否则就会注册Leds driver失败。
Example platform data:
Note - chan_nr can have values between 0 and 8.
static struct lp55xx_led_config lp5523_led_config[] = {
{
.name = “D1”,
.chan_nr = 0,
.led_current = 50,
.max_current = 130,
},
…
{
.chan_nr = 8,
.led_current = 50,
.max_current = 130,
}
};
static int lp5523_setup(void)
{
/* Setup HW resources */
}
static void lp5523_release(void)
{
/* Release HW resources */
}
static void lp5523_enable(bool state)
{
/* Control chip enable signal */
}
static struct lp55xx_platform_data lp5523_platform_data = {
.led_config = lp5523_led_config,
.num_channels = ARRAY_SIZE(lp5523_led_config),
.clock_mode = LP55XX_CLOCK_EXT,
.setup_resources = lp5523_setup,
.release_resources = lp5523_release,
.enable = lp5523_enable,
};